The invention is related to a vacuum brake power booster of a known type having a booster housing, preferably made of sheet or plate metal and with an electrical travel sensor for monitoring the position of a movable wall furnishing the boosting power, the sensor fixed in an opening providing in the booster housing by means of a sensor receptacle which is formed with locking projections extending out from the periphery of the opening and which is sealed off with respect to the booster housing by means of an elastic seal.
A reliable sealing of the sensor receptacle with respect to the booster housing is of prime importance for a smooth functioning of the brake power booster. A force acting on the seal is required which leads to a deformation of that seal and depends in part, on the thickness of the material of which the booster housing is formed. In order to eliminate the effect of the material thickness, a two-part sensor receptacle has been devised whose parts are coupled to each other by means of a threaded connection so as to be adjustable. The considerable manufacturing and assembly costs of this complex, prior-art sensor receptacle is a disadvantage.
It is therefore, the object of the present invention to improve a vacuum brake power booster by providing a sensor receptacle allowing manufacture and assembly at low cost but which is universally applicable for different material thickness of the booster housing.